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        <p>Library Version 11.2.5.3</p>
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          <th width="60%" align="center">Chapter 3. Transaction Basics</th>
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            <h2 class="title" style="clear: both"><a id="autocommit"></a>Auto Commit</h2>
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      <p>
            While transactions are frequently used to provide atomicity to
            multiple database 
            <span>
                    or store
            </span>
            operations, it is sometimes necessary to perform
            a single database 
            <span>
                    or store
            </span>
            operation under the control of a transaction.
            Rather than force you to obtain a transaction, perform the single 
            write operation, and then either commit or abort the transaction,
            you can automatically group this sequence of events using
            <span class="emphasis"><em>auto commit</em></span>.
        </p>
      <p>
            To use auto commit:
        </p>
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        <ol type="1">
          <li>
            <p>
                        Open your environment and your databases 
                        <span>
                            or store
                        </span>
                        so that they support
                    transactions.  See <a class="xref" href="enabletxn.html" title="Chapter 2. Enabling Transactions">Enabling Transactions</a> 
                    for details.
                </p>
          </li>
          <li>
            <p>
                    Do not provide a transactional handle to the method that is
                    performing the database 
                        <span>
                            or store
                        </span>
                    write operation.
                </p>
          </li>
        </ol>
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      <p>
            Note that auto commit is not available for cursors. You must always
            open your cursor using a transaction if you want the cursor's
            operations to be transactional protected. See 
            <a class="xref" href="txncursor.html" title="Transactional Cursors">Transactional Cursors</a> for details on using
            transactional cursors.
        </p>
      <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
        <h3 class="title">Note</h3>
        <p>
                Never have more than one active transaction in your thread
                at a time. This is especially a problem if you mix an
                explicit transaction with another operation that uses auto
                commit. Doing so can result in undetectable deadlocks.
            </p>
      </div>
      <p>
            For example, the following uses auto commit to perform the database write operation:
        </p>
      <pre class="programlisting">package db.txn;

import com.sleepycat.db.Database;
import com.sleepycat.db.DatabaseConfig;
import com.sleepycat.db.DatabaseEntry;
import com.sleepycat.db.DatabaseException;
import com.sleepycat.db.Environment;
import com.sleepycat.db.EnvironmentConfig;

import java.io.File;

...

Database myDatabase = null;
Environment myEnv = null;
try {
    EnvironmentConfig myEnvConfig = new EnvironmentConfig();
    myEnvConfig.setInitializeCache(true);
    myEnvConfig.setInitializeLocking(true);
    myEnvConfig.setInitializeLogging(true);
    myEnvConfig.setTransactional(true);

    myEnv = new Environment(new File("/my/env/home"),
                              myEnvConfig);

    // Open the database.
    DatabaseConfig dbConfig = new DatabaseConfig();
    dbConfig.setTransactional(true);
    dbConfig.setType(DatabaseType.BTREE);
    myDatabase = myEnv.openDatabase(null,              // txn handle
                                    "sampleDatabase",  // db file name
                                    null,              // db name
                                    dbConfig);
    String keyString = "thekey";
    String dataString = "thedata";
    DatabaseEntry key = 
        new DatabaseEntry(keyString.getBytes("UTF-8"));
    DatabaseEntry data = 
        new DatabaseEntry(dataString.getBytes("UTF-8"));

    // Perform the write. Because the database was opened to 
    // support transactions, this write is performed using auto commit.
    myDatabase.put(null, key, data);

} catch (DatabaseException de) {
    // Exception handling goes here
} </pre>
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